10th Class Chemistry 3rd Quarter Book Paper

Q1. Multiple choice questions (Attempt all · 12 × 1 = 12)

1. Which of the following best defines polymers?
   1. Small molecules bonded together to form large molecules
   2. Large molecules built up from many smaller molecules called monomers
   3. Simple molecules consisting of one type of atom
   4. Large molecules made up of metals and non-metals
2. Alcohol swabs are commonly used to disinfect the skin:
   1. After meals
   2. Before injection or surgery
   3. During exercise
   4. For cosmetic use only
3. Which of the following is an example of a carboxylic acid?
   1. Ethanol
   2. Ethanoic acid
   3. Ethyl acetate
   4. Methanol
4. In Baeyer’s test, saturated hydrocarbons show:
   1. No reaction
   2. Colourless solution
   3. Formation of precipitate
   4. Blue colouration
5. Polymers are formed by joining together many:
   1. Ions
   2. Atoms
   3. Monomers
   4. Molecules
6. Corn-based ethanol reduces greenhouse gas emissions by roughly:
   1. 10–20%
   2. 25–30%
   3. 40–50%
   4. 60–70%
7. The oxidizing agents used to convert alcohols to carboxylic acids are:
   1. HCl and H₂SO₄
   2. KMnO₄ and K₂Cr₂O₇
   3. NaOH and CaO
   4. HNO₃ and NaCl
8. The general formula of alkanes is:
   1. CnH2n
   2. CnH2n+2
   3. CnH2n-2
   4. CnHn
9. Incineration of plastics can release:
   1. Oxygen
   2. Fertilizers
   3. Harmful chemicals and greenhouse gases
   4. Water vapours only
10. Alcohols are effective in sanitizing:
    1. Metals only
    2. Surfaces and hands
    3. Food items
    4. Plastic materials
11. What is the product of the reaction between ethanoic acid and sodium carbonate?
    1. Sodium propanoate
    2. Sodium hydroxide
    3. Sodium chloride
    4. Sodium acetate
12. The general formula of alkenes is:
    1. CnH2n+2
    2. CnH2n
    3. CnH2n-2
    4. CnHn